Pre-Zika Public Attitudes Toward Genetically Modified Mosquitoes

Amesh A. Adalja, MD, FACP, FACEP, FIDSA, June 10, 2016

Even before the advent of the Zika virus outbreak in the Western Hemisphere, the spread of 2 other Aedes aegypti mosquito–borne diseases—dengue and chikungunya—were of major concern for the region. The spread of these viruses is almost exclusively curtailed by aggressive control of vector mosquito populations using a variety of conventional methods. In recent years an additional and novel method that uses genetically modified mosquitoes has become available. This process involves the release of sterile male mosquitoes, thereby reducing mosquito population levels and diminishing the risk of mosquito exposure for humans in the area.

However, the release of genetically modified mosquitoes is not without controversy and, for many people, is closely linked with broader societal concerns regarding genetically modified organisms (GMOs) and gene drives, the subject of a just-released National Academies report.1 Because of this context, public acceptance of and engagement with any release of these mosquitoes will be necessary.

In order to gauge the public’s attitudes toward this technology, my colleagues Crystal Boddie, MPH, Meghan McGinty, PhD, and Tara Kirk Sell, PhD, and I conducted a survey of the general public in 1 Key West neighborhood, an area of the country in which local transmission of dengue has occurred. The resulting paper was just published in PLoS Currents: Outbreaks.2

Pre-Zika Perceptions

The survey was done between July and November 2015 and consisted of a series of questions focused on knowledge of mosquito control methods, dengue, and chikungunya, as well as demographic variables. Because of the timing, the results of the survey provide a unique insight into pre-Zika perceptions of genetically modified mosquitoes in an at-risk neighborhood.

Though most respondents believed mosquitoes to be a nuisance and thought that mosquito population control was warranted, the majority were not supportive of genetically modified mosquito release to achieve that goal.

Delving deeper into the data in order to determine what variables might be linked to opposition to or support of the use of genetically modified mosquitoes, we undertook an adjusted logistic regression analysis. In the final model, we found 2 factors to be significantly associated with opposition to or support of the release of genetically modified mosquitoes: female sex (OR 7.47) and a perception of risk of acquiring an infection (OR 0.38).

The Influence of Zika

While the pre-Zika timing of our study may render the findings largely historical, the insight into what drives opposition to or support of genetically modified mosquito release does provide useful information for current and future responses to Zika, dengue, and chikungunya.

Because the biggest public health threat surrounding Zika is to pregnant women, the fact that female sex was strongly predictive of opposition to this technology is an interesting finding. Women may, in the face of Zika, recalibrate their evaluations of genetically modified mosquitoes and become less opposed. Similarly, the fact that perceived individual risk of dengue or chikungunya predicted support of genetically modified mosquitoes has likely also been influenced by ubiquitous media coverage of Zika and could alter levels of overall support.

As the release of genetically modified mosquitoes is contemplated as an Aedes aegypti control strategy, engaging the public and addressing concerns with a data-driven approach may help to optimally implement this novel technology. Additionally, as the capacity for using genetically engineered organisms to control other infectious diseases increases and moves beyond mosquitoes, to, for example, white-footed mice and Lyme disease, similar themes may be evident.